Method of making a denture



June 15 1926.

1,589,083 c. L. ALEXANDER METHOD OF MAKING A DENTURE Filed April 2, 1924INVENTOR.

MA TTORNEIYI Patented June 15, 1926.

CHARLES LEE ALEXANDER, OF CHARLOTTE, NORTH CAROLINA.

METHOD OF MAKING A DENTURE.

Application filed April 2, 1924. Serial No. 703,768.

This invention relates to a method, of making a denture and has for anobject to provide a, process for fitting a denture to the mouthaccurately, quickly and convenient 1y to produce a denture comfortablefor use and one which will retain its position firmly.

A further object of the invention is a method whereby a denture isproduced by two impressions taken in the mouth of the patient, the firstfor forming a model from which a denture is made in very nearly completeform but without accuracy of lit, the second impression being takendirectly in the denture itself and insuring absolute accuracy. I

A further object of the invention is the process of making a denturewhereby a base plate is roughly fitted to the oral cavity insubstantially the usual and ordinary manner and then a furtherimpression taken in the mouth directly in the partially completeddenture, the filler material of such second impression being removedalong withrthe base plate in process of vulcanizing.

With these and other objects in view, the invention comprises certainnovel steps in the production of a denture as will be hereinafter morefully described and claimed.

As illustrating the method, drawings are herewith submitted wherein-Figure 1 shows a model constructed from an impression made insubstantially the usual and ordinary manner now practiced in the art.

Figure 2 is a perspective view of the base plate modeled roughly uponthe model shown at Figure 1 but without accuracy of fit.

Figure 3 shows the teeth set up on the base 40 plate in substantiallythe usual and ordinary manner, the buccal and lingual sides or surfacesbeing completed in this form but the palatal "side or surface beingstill untitted to the palatal and alveolar ridges.

Figure 4 is a transverse sectional view taken through the piececompleted to the form shown at Figure 3 with the palatal. side of thebase plate covered with a thin coating of thin impression material inplastic condition, such for instance as plaster of Paris mixture, or anyother material which will take and hold an accurate and perfectimpression. p I p I Figure 5 is a view similar to Figure l, the

555 impression material having taken the term the palatal and. alveeiarridge Figure 6 is a transverse sectional view showing unitary structureafter vulcanizing.

-Like characters of reference indicate corresponding parts throughoutthe several views.

In carrying out the process which forms the subject matter of thisapplication, an impression is taken in the mouth of the patient inimpression material in the usual manner, such impression material beingany usual and ordinary material used in the art or preferred by theparticular manipulator. Employing this impression thus produced, whichis a step well known in the practice of 7 the art, a model is made,which said model is shown at A, Figural. The making of this impressionand the construction of this model need not be done in a particularlycareful manner and the model may not, therefore, correspond identicallywith the jaw structure.

Over this model A, a base plate B is formed. This base plate is made ofmaterial well known in the art and is contoured by softening with heat,permitting it to be contoured roughly to the model A. In the productionof this base plate, no great accuracy of fitting is necessary but it isdesirable that the base plate be constructed of ma- 35 terial presentinga considerable degree of rigidity when cold. This is to prevent warpingor buckling of the piece during its later processing.

Upon this base plate B, the teeth C are set up in substantially theusual and ordinary manner by the use of wax or the like,

and the piece is completed to form so far as the buccal and lingualsurfaces are concerned as in the present practice. The showing of theteeth G in the drawings is not intended as in any way a limitation uponthe present invention or indicating in any manner the particular styleor type of teeth which should be employed and the operator 199 isenabled in this process to use any form, type or model of teeth that hisfancy may chooseor his judgment may dictate.

As shown in Figure 3, the denture is complete in wax or compound formaccording to the usual practice of such manipulation with the exceptionof the surface engaging the alveolar ridges or palatal ridges, if asuperior. denture. As shown in the drawings, a superior denture isdisclosed but it no is to be understood that an inferior denture willfollow like process of manganese and any reference herein to contactwith the palate or palatal ridges is not to be understood as in any waylimiting the invention to a superior denture.

The piece is now in condition for the second impresion at which pointthe invention involved in the present invention begins. This secondimpression is formed by covering the palatal surface of the base plate Bwith some impression material indicated at D. It has been found inpractice that plaster Paris mixed to thin consistency in water andspread in a thin coating over the palatal surface of the base plate isan acceptable impression material and the further steps will bedescribed in terms of plaste'r Paris for impression without in any waylimiting the invention to this particular impression material.

The impression material D being properly applied upon the palatalsurface of the base plate B, as shown at Figure 4, the piece in itsentirety is promptly placed in the mouth of the patient and forced withconsiderable pressure against the palatal and alveolar ridges so that anabsolutely accurate impression of the various contours are received andretained in this impression material, as shown at Figure 5.

After a sufficient lapse of time for the proper hardening of theimpression material, the piece is removed from the mouth and the excessplaster trimmed away. A little wax is run around as margin to preventthe plaster from scaling in further manipulation, The plasterfillerimpression is coated with astaine'd or unstained separating fluid, whichbeing done, the piece is ready to flask in the usual manner.

After the investment material in theflask has hardened, heat is appliedto make itpossible to, open up the flask without breaking the plaster,also to soften the base plate and wax to such a degree as to permit itsremoval. The removal of this wax base plate and filler leaves the teethin the investment material of the flask and vulcanizable rubber ispacked in, in the usual manner of such procedure and the flask closedunder pressure and is ready for vulcanizin'g,

Ordinarily, the impression material carried by the base plate comes awayfrom the flask with the base plate leaving the investment material cleanbut, in case it should adhere to the surface of the investment material, it is removed by any suitable instrument.

,The steps of setting up the teeth by the employment of the articulatorand other well known steps in the construction of such denture has notbeen described as all of those steps are within the well known practicein the art. Also the manipulation of investment materials, the uses ofmodels, the prop er degree of heat for separation of the flask andplastic in'ipression material, vulcanizing and the like, are so wellknown in the art as to be mere surplusage in the specification directedto the present invention and are, therefore, left to the practitionerfor carrying out.

While this method has been described as a method for the construction ofa complete denture, it is obvious that a partial denture can be treatedin like manner.

hat I claim to be new is;

1. A method of making a denture consisting in producing a model from animpression, erecting upon the model a denture in wax including anormally rigid wax base plate, complete with the exception of thefitting of the palatal and alveolar surfaces, producing an impressiondirectly from the mouth directly into said base plate, investing thepiece so constructed, removing the waxy material and base plate togetherwith the filler impression material, replacing the removed material byvulcanizable material and vulcanizing the entire piece as a homogeneousstructure.

2. The method of making a denture consisting in producing a. denturecomprising a normally rigid wax base plate roughly fitted to the mouthand supporting teeth secured thereon, taking a second impression fromthe mouth directly into the base plate, replacing the wax impressionmaterial and the base plate with a vulcanizing material, and vulcanizingthe entire piece as an unitary structure.

The method of making a denture consisting in fitting roughly a waxdenture including a normally rigid wax base plate to an initial model,taking an impression upon the denture so partially completed, investingthe piece, removing the waxy and impression material from theinvestment, replacing with a vulcanizable material, and vulcanizing.

4. The method of making a. denture consisting in producing from animpression a model, roughly fitting anormally rigid wax base plate uponthe model, setting up the teeth on the base plate by the use of wax,spreading over the base plate a layer of plastic impression material,inserting the piece into the mouth to take animpression in theimpression material, producing a second model as a part of theinvestment, removing the tiller impression material, the base plate. andthe material employed for setting up the teeth, replacing the removedmaterial by a vulcanizing material, employing pressure to contour thevulcanizable material to an exact complement to the jaw, and imbed theartificial teeth therein, and rulcanizing as an unitary structure.

5. The method of making a denture con-- sisting in making a denture,roughly fit ing the jaw of wax like material including a normally rigidWax base plate, setting up the teeth on said Wax-like material, takingan impression from the mouth directly upon the Wax model, investing thepiece, removing the WaX, the impression material and base plate,replacing With a vulcanizable material-l, closing together theinvestment under pressure to force the said vulcanizable material toconform to the investment cavity, and. vulcanizing in such closedposition.

In testimony whereof I afiix my signature.

CHARLES LEE ALEXANDER.

